the last of a series of events that causes an angry or violent reaction When he didn’t come home that night, it was the last straw. капля, переполнившая чашу

I definitely agree with victoriaenglish's definition. There is another very closely related saying that we sometimes use in the US: We say "the straw that broke the camel's back." To understand this saying, imagine a camel (animal of burden with two humps on its back) that is carrying so much straw that it is having a hard time walking! The owner of the camel continues to put straw on the back of the camel over a period time. Finally, the owner put one last little piece of straw on the back of the camel... That straw breaks the camel's back. Because of that expression, we can say "thats it! That is the last straw!!" :) ~ Jonathan Wesley Dudzik

Something someone does that pushes you just a bit too far, and makes further continuance of the situation near impossible. See definition: "a further difficulty or annoyance, typically minor in itself but coming on top of a whole series of difficulties, that makes a situation unbearable."